The present invention relates to a lighting device able to generate a light beam which forms a defined and uniform rectangular pattern at the work area, e.g. for illuminating pedestrian crossings or for use in other applications where an illumination pattern of the above indicated type is required, such as in the case of motor-vehicle fog lamps, or for illuminating paintings or long aisles in industrial buildings, etc.
The object of the present invention is that of providing a device of the above indicated type which is able to form a rectangular pattern of relatively wide dimensions starting from a device of reduced dimensions, which may have any shape, including the circular shape, and with a relatively simple and inexpensive structure.